CROSS-MATCH-COMPATIBLE PLATELETS IMPROVE CORRECTED COUNT INCREMENTS IN PATIENTS WHO ARE REFRACTORY TO RANDOMLY SELECTED PLATELETS

BACKGROUND: HLA-matched platelets and crossmatch-compatible platelets are used to support thrombocytopenic patients who are refractory to ra ndomly selected platelets. Data supporting the effectiveness of crossm atch-compatible platelets are limited, being essentially restricted to the subset of refractory patients previously shown to be alloimmunize d. The authors' hospital does not test for alloimmunization. To determ ine the effectiveness of crossmatch-compatible platelets in an unselec ted group of refractory patients, the use of such platelets for all pa tients who are refractory to random-donor platelets was reviewed. STUD Y DESIGN AND METHODS: All patients who received crossmatch-compatible platelets between January 1991 and May 1994 were retrospectively revie wed. All study patients were refractory to random-donor platelets, hav ing two consecutive corrected count increments (CCIs) of <10,000. A so lid-phase red cell adherence method was used for platelet crossmatchin g, and CCI was used to monitor the effectiveness of each platelet tran sfusion. RESULTS: A total of 475 crossmatch-compatible platelet compon ents were administered to 66 evaluable patients who were refractory to random-donor platelets. A significant improvement was found in the me an CCI when crossmatch-compatible platelets were compared with randoml y selected platelets (p<0.0001): an increase of 8000 +/- 6100 (mean +/ - SD). In 59 percent (39/66) of the patients, the mean CCI improved to at least 7,500 and in 41 percent (27/66) to at least 10,000. If the 1 0 patients for whom crossmatch-compatible platelets were not identifie d are included, the mean CCI in 51 percent(37/76) of the refractory pa tients improved to at least 7,500; in 36 percent (27/76), it improved to at least 10,000. The effectiveness of crossmatch-compatible platele ts did not decline with continued use. CONCLUSION: Crossmatch-compatib le platelet components significantly improve the mean CCI for approxim ately one-half of patients who are refractory to random-donor platelet s, even when the patients are not preselected for having alloimmunizat ion to explain their refractory state.